Active research and development are recently in progress for practical realization of a three-dimensional display system allowing for visual recognition of three-dimensional images for viewers.
Three-dimensional image display systems have been roughly classified into (1) so-called 3-D glasses type three-dimensional image display systems and (2) naked eye three-dimensional image display systems, where according to the system (1) an image display apparatus displays images including left-eye images and right-eye images with disparity added thereto, and viewers wear special kind of glasses (an optical aid) that allow left-eye images to be visually recognized by the left eye while allowing right-eye images to be visually recognized by the right eye, and according to the system (2), it is so configured that three-dimensional images are visually recognizable without the use of special glasses.
The 3-D glasses type three-dimensional image display systems (1) are further classified into several kinds of systems. The following systems are examples thereof: (a) a so-called anaglyph system in which left-eye images and right-eye images are created in two different colors, e.g., red and blue, the system involving use of glasses including a red color filter for one eye and blue color filter for the other eye (refer to, for example, Japanese Patent Laying-Open No. 2006-129225 (PTL 1)); and (b) a system in which left-eye images and right-eye images are displayed in differently polarized conditions, the system involving use of glasses provided with polarization filters for separating left-hand and right-hand images (refer to, for example, paragraphs [0038] to [0054] of Japanese Patent Laying-Open No. 2008-292577 (PTL 2); and (c) a system in which left-eye images and right-eye images are displayed alternately, the system involving use of liquid-crystal shutter glasses for performing opening/closing operation in alternative manner between the right and the left in conjunction with switch of images (refer to, for example, paragraphs [0055] to [0066] of PTL 2).
There are also polarizing devices with patterns provided in a plurality of polarization regions that are different in direction of transmission axis of polarization (refer to, for example, paragraphs [0002] to [0003] of WO 2005/096041A (PTL 3)).